I am converting some Fortran77 codes into Fortran90. I want to make it faster by taking advantage of the features in Fotran90 - 'forall' and 'where' for array operations and intrinsic function - 'dot_product' for vector multiplication. But when I used program profile software to analyze the program, I got slower result for these changes, especially the dot_product function.
Does anybody know if there are advantages in Fortran90 which can be utilized to upgrade Fortran77 code? Thanks.